Filter shaker for suction cleaners



Feb. 12, 1952 D. G. SMELLIE FILTER SHAKER FOR SUCTION CLEANERS 2SHEETSSHEET 1 Filed Dec. 28, 1946 INVENTOR. Donald (iSmelZie B M 5'. MM

9 ATTORNEY.

v Viv Feb. 12, 1952 2,585,508

FILTER SHAKER FOR SUCTION CLEANERS Filed Dec. 28, 1946 2 SHEETSSHEET 2lo INVENTOR. Donald G. SmQZZie Y w ATTORNEY.

Patented Feb. 12, 1952 FILTER SHAKER FOR SUCTION CLEANERS Donald G.Smellie, Canton, Ohio, assignor to The Hoover Company, North Canton,Ohio, a corporation of Ohio Application December 28, 1946, Serial No.718,959

7 Claims.

This invention relates to suction cleaners in general and moreparticularly to a new and improved filter support and filter shakermechanism.

Filter shakers for suction cleaners heretofore available fall into twobroad categories, i. e. those which support the filter under slighttension permitting the filter to be agitated gently to dislodge dirt,and those which tension the filter walls abruptly with a sharptensioning force. Shakers within the first mentioned category areineffective and of little utility as applied to suction cleaners whilethe second type require the use of a strong walled filter which willwithstand the sharp snapping action as well as prolonged strongtensioning between shaking operations.

The present invention provides a construction possessing the advantagesof both types while avoiding the disadvantages of either. A singlespring is utilized to energize the shaker as well as to return themanual actuator mechanism.

Moreover, the single spring is arranged to maintain the filter lightlytensioned normally and to impart a strong and abrupt tensioning force tothe filter briefly during the shaking operation. Upon the conclusion ofthe shaking operation, however, the strong temporary shaking tensionprovided by the spring is automatically decreased to an amount necessaryto support the filter walls under slight tension. A major part of thedecrease in tension is employed to return the actuating mechanism to itsnormal position in readiness for another shaking operation.

Accordingly, it is an objective of the invention to provide a new andimproved filter shaking mechanism.

Another object is the provision of a snapaction type shaker employing asingle spring.

Yet another object is to utilize a single spring to energize a filtershaker and to return the manual actuator therefor.

Still another object is the provision of a filter shaker in which thetension on the filter is decreased automatically and at a timesubsequent to the conclusion of the shaking operation.

Further objects and advantages of the invention will become apparentfrom the following specification and drawings in which:

Figure 1 is a vertical sectional view through a suction cleanerincorporating the invention;

Figure 2 is a horizontal sectional view on line 2-2 of Figure 1; and

Figure 3 is a fragmentary sectional view on line 3-3 of Figure 2.

The invention is shown as incorporated in a suction cleaner of the tanktype having a casing l supported upon a pair of runners H. The suctioninlet end of the casing is closed by a removable end cap l2 forming anairtight closure for casing H3. The lower side of cap. [2 is providedwith interlocking tabs l3 while the top side I is releasably held inplace by a toggle latch l4.

The exhaust end of the casing is closed by a removable end cap l5. CapI2 is provided with the usual suction hose coupling I6 while the exhaustcap carries a similar coupling l1. Any well known form of multi-stagemotor-fan unit l8 may be appropriately supported near the exhaust end ofeasing H]. A convenient carrying handle I9 is attached to the upper sideof the casing having an electric control switch 20 at one end thereof.

An air pervious filter bag of cloth or other suitable material 2l hasits open inlet end secured to a flanged opening in partition 22 by meansof a clamp 23. The closed end of the filter is secured to a sup ortingspider 24 by a split ring spring keeper 25.

The shaker mechanism for the filter comprises a bed-plate member 25riveted to the inner, lower side of casing l0. Parallel links 21 arepivotally secured between the opposite sides of the rear end ofbed-plate 2G and the ends of yoke 28 forming a part of spider 24. Asindicated by Figure 2, only one pair of links 2'! is required for oneside of the filter support while the opposite side of the end of theyoke may be supported by a single link 21. The forward link on eitherside of the filter may be joined into a U-shaped member and the upperend of each leg may be pivotally connected to yoke 28. The lower, bightportion of this U-shaped member is pivotally supported betweenupstanding ears of bed-plate 26 by a pivot pin 29. A single coiledspring 30 surrounds pivot pin 29.

As will be clear from Figure 2, spring 30 is wound in oppositedirections from its mid-portion 3| and its outer ends 32 are hookedabout the forward side of links 21 so as to urge the links to rotatecounterclockwise. The manner in which the mid-portion 3| of the springis supported will be described below. From the foregoing, it will beclear that spring 30 acts through links 21, yoke 28 and spider 24 tomove the closed end of the filter bag to the left so as to maintain thewalls thereof under tension.

The shaker mechanism for shaking the filter vigorously to dislodge dirtwillnow be described. The forward end 33 of bed-plate 26 is of invertedU-shape in cross section to provide a raceway 3 for a slide member 34.An overturned tab 35 projecting upwardly from slide 34 extends throughan opening in the bed-plate and is secured to a wire bail 36 the ends ofwhich are pivotally connected to an intermediate point 31 on links 21.

The actuator and trigger release mechanism operable to collapse thefilter and then release it for abrupt tensioning includes a foot pedal39 having one end pivotally supported upon the exterior under side ofcasing l and bed-plate 26 at 45. Pivot pin 49 is rigidly secured to thefoot pedal as well as to an arm 4| positioned inside casing Ill. Theintermediate portion of a dog 42 is pivotally connected to arm 4| by apin 43. The rearwardly extending arm 44 of the dog abuts the side of arm4|, while its forward nose portion 44 is positioned to normally abut aroller 45 carried by the forward end of slide 34. Torsion spring 46surrounds pin 43 and is interconnected between dog 42 and arm 4! to urgethe dog counterclockwise.

From the foregoing, it will be clear that when the foot pedal is rotatedclockwise it carries arm 4| in the same direction causing nose .4 of dog42 to abut roller 45 and move slide 34 in a direction to collapse thefilter against the action of spring 30.

The automatic means for reducin the tension on spring 3|] after thefilter has been returned to its taut condition, as well as for returningthe foot pedal to its initial starting position, will now be described.Essentially, the mechanism for accomplishing this purpose comprises aconnection of any suitable type between the intermediate portion 3| ofspring 3|] and the manually operab1e mechanism for collapsing thefilter. This connection may take various forms but as here showncomprises a toothed rack 41 slidably supported on the lower inner sideof easing It by a, guide plate 48. The toothed end of the rack isengageahle with a toothed sector 49 formed as a part of arm 4|. Theopposite end of rack 4'! has a lost motion connection 50 with leverpivotally supported at 52 on bed-plate 26. The free end of lever 5| isconnected to the downturned, intermediate portion 3| of spring 30 bymeans of a link 53.

It will thus be apparent from Figure 2 that as foot pedal 39 isdepressed, rack 41 is moved longitudinally to the left rotating link 5|clockwise to increase the tension on torsion spring 39. At the sametime, nose 44 of dog 42 moves slide 34 to the right to collapse thefilter and to increase the tension on the outer ends 32 of spring 39.However, due to the difference in the effective lever arms acting on theintermediate portion 3| and the outer ends 32 of spring 39, stressincrease on the intermediate portion 3| of the spring occurring on thedepression of foot pedal 39 is appreciably less than that applied to theouter ends 32.. It will also be understood that in normal operation theuser depresses the foot pedal and holds it depressed for a briefinterval after nose 44 has by-passed roller 45 to release bail 36. As aconsequence, the outer ends of spring 30 snap the filter taut before theoperator can possibly remove his foot from the pedal. Accordingly, thefilter is held taut under the stresses imposed on ends 32 of spring 39plus the additional stress placed on intermediate portion 3| thereof asthe result of the linkage connection with foot pedal 39., Thisadditional stress is utilized to return the foot pedal and arm 4| to itsinitial starting position. These important features of the iIiVQIllQI} 4will be better understood from the more detailed description of the modeof operation set forth below.

Operation Let us assume that a cleaner is assembled as shown in Figurel. The operator connects the flexible hose to either inlet coupling Itor exhaust coupling depending upon whether it is desired to clean bysuction, as normally, or by blowing. After the cleaner has been inoperation for a period of time, a body of dirt will have collected infilter 2|. By virtue of the present invention, the filter can be emptiedand restored to its original clean condition quickly and simply. First,the operator unlatches and removes end cap it. The cleaner is then up-ended onto the open end whereupon the major portion of the dirt fallsout into a receptacle or onto a paper previously laid beneath the openend.

. To remove dirt adhering to the side walls of the filter, the usersteps onto pedal 39 rotating it downwardly toward the'fioor until arm 4|abuts a stop 54 struck upwardly from bed-plate 26. R0- tation ofarm 4|moves dog 42 clockwise, as viewed in Figure 2, so that nose 44 strikesroller 45 on slide 34. This moves the slide downwardly in guideway 33until nose 44 over-rides roller 45. As the slide 34 moves downwardly, itcarries bail 36 and parallel linkage 21 downwardly very considerablyincreasing the stress on spring 30. At the same time, yoke 28 and theinner end of the filter bag is moved downwardly to collapse the sidewalls of the filter. As arm 4| rotates clockwise it also moves rack 41.upwardly to rotate lever 5| clockwise, further increasing the stress onthe intermediate portion 3| of spring 3! However, as explained above,the stressincrease imposed upon the intermediate portion of the springby rack 41 is appreciably less than that imposed upon the outer end bymovement of slide 34.

At the instant nose 44 over-rides roller 45, slide 34 is released andthevery considerable energy stored in spring acts through links 21 and yoke28 to snap the filter taut sharply and abruptly.

This action is highly effective in dislodging dirt clinging to theinterior of the filter. Moreover, the snapping of the filter occursinstantaneously and before the user can remove his foot from pedal 39.As he does so, the additional unrelieved stress on sprin 36 acts throughlever 5| and rack 41 to return arm 4| and foot pedal 39 to their initialstarting position. As this occurs, dog 42 rotates clockwise permittingnose 44 to under-ride roller 45 and assume its normal positionthereabove as illustrated in Figure 2. Thus, it will be readilyunderstood that intermediate portion 3| of spring 30 moves in adirection to decrease the tension thereon. This decrease in tension isreflected through links 2'! and yoke 28 with the result that the filteris then under sufllcient pressureto prevent slackness in the filterwalls and to maintain the same under slight tension.

If a single operation of the shaker is not completely eifective torestore the full efficiency of the filter, the shaker mechanism may beoperated one or more times until the filter is completely freed ofclinging dirt. Thereafter the cleaner is returned to a supportingposition upon runners II and and end cap 52 is replaced restoring thecleaner to duty for further cleaning.

While only a single embodiment of the invention has been described indetail, it will be readily apparent that the novel features thereof maybe incorporated various arrangements without departing from the spiritof the invention or the inventive principles thereof What is claimed is:

1 In combination, a suction cleaner casing, a filter bag within saidcasing having one end supported thereby, linkage means connected to theopposite end of said bag including a spring for normally biasing saidbag in a direction to maintain the walls thereof under slight tension,manually operable means connected to said spring and linkage means forcollapsing said filter bag and simultaneously stressing said spring andincluding a releasable connection which opens after a predeterminedmovement of said manually operable means whereby the energy stored insaid spring operatesto tension said filter abruptly to dislodge dirttherefrom, and linkage means providing a permanent connection betweensaid spring and said manually operable means for additionally stressingsaid spring as said filter is collapsed whereby, upon the opening ofsaid releasable connection, the energy stored in said spring during thecollapse of said filter is available to tension the same abruptly, toreturn said manually operable means to the initial position thereof andto reclose said releasable connection.

2. In combination, a suction cleaner casing, a filter within said casinghaving one portion thereof supported by said casing, filter shakermechanism comprising a lever pivotally supported by said casing andhaving one end thereof connected to said filter so as to tension thewalls thereof substantially uniformly, spring means having one endconnected to said lever and urging the same in a direction to tensionsaid filter slightly, manually operable means movable between a normalrest position and a second position, means including a releasableconnection interconnecting said lever and said manually operable means,said releasable connection being operable to open after a predeterminedmovement of said manually operable means, and means connecting theopposite end of said spring means and said manually operable meanswhereby movement of said manually operable means away from the restposition thereof collapses said filter and stresses said spring meansuntil said releasable connection opens whereupon the energy stored insaid spring means tensions said filter abruptly to dislodge dirt,returns said manually operable means to the rest position thereof andcloses said releasable connection.

3. In combination, a suction cleaner casing, an elongated filter bag insaid casing having an open end supported thereon, a U-shaped memberstraddling the closed end of said filter having its free ends secured tothe closed end of the filter and its bight portion pivotally supportedwithin said casing, spring means biasing said U-shaped member in adirection to tension the walls of said filter, a bail member connectedto the legs of said U-shaped member, a manually operable lever supportedon said casing, means providing a normally closed releasable connectionbetween said bail member and said lever, said releasable connectionbeing operable to open when said lever is moved through a predeterminedangle, and linkage means having one end connected to said spring meansand the opposite end connected to said manually operable lever so thatsaid spring means biases said lever to a normal rest position in whichsaid releasable connection i closed,

whereby said lever is operable to collapse said filter against the biasof said spring means by moving the closed end of said filter toward said6 open end until'said releasable connection opens whereupon the energystored in said spring means snaps said filter taut abruptly, returnssaid lever to the rest position thereof and closes said releasableconnection.

4. In combination, an air pervious-filter, stationary means forsupporting one end of said filter while leaving the remainder of saidfilter free for shaking, a shaker mechanism for shaking said filter todislodge dirt therefrom comprising manually operable means movablebetween a normal rest positionand an operated position, linkage meansinterconnecting the unsupported part of said filter and said manuallyoperable means, said linkage means including a spring urging saidmanually operable means to the rest position thereof and holding thewalls of said filter extended and under slight tension, and rigidlinkage means interconnecting the unsupported part of said filter andsaid manually operable means for collapsing: said filter against theopposition of said spring, said rigid interconnecting means including areleasable connection which opens when said manually operable means hascollapsed said filter to a predetermined position whereby said springsnaps said filter taut abruptly to dislodge dirt therefrom andthereafter returns said manually operable means to the rest positionthereof and closes said releasable connection.

5. The combination defined in claim 4 wherein said manually operablemeans includes a lever pivotally supported intermediate the ends thereofand wherein said spring biased linkage means and said rigid linkagemeans are connected to said lever on the opposite sides of the pivotalsupport therefor.

6. In combination with a suction cleaner casing having an elongatedfilter bag therein, means connecting the open end of said bag to saidcasing, shaker mechanism connected to the closed end of said bagcomprising manually operable means supported on said casing and beingmovable over a limited range between a normal rest position and anextended position, spring means having one end thereof connected to theclosed end of said bag and the other end connected to said manuallyoperable means and operable normally to hold said manually operablemeans in said rest position and the Walls of said bag extended underslight tension, and linkage means connected in parallel with said springmeans between the closed end of said bag and said manually operablemeans, said linkage means including a normally closed releasableconnection operable to open as said manually operable means approachesthe extended position thereof whereby movement of said manually operablemeans by an externally applied force collapses said filter bag towardthe open end thereof against the opposition of said spring means untilsaid releasable connection opens whereupon the energy stored in saidspring means tensions the walls of said bag abruptly and thereafterreturns said manually operable means to said rest position and closessaid releasable connection.

'7. In combination with a suction cleaner having a filter mountedtherein, shaker mechanism for said filter normally holding said filterextended but operable to collapse said filter and tension it abruptly,comprisin a movable support for one end of said filter, a manuallyoperable lever, members providing a first and a second parallelconnection between said support and said lever, a normally closedreleasable conne ion said first parallel connection. means for openingsaid releasable connection when said filt r ha e n co l psed to &predetermined position, and a normally substantially relaxed springinterposed in and forming part of said second parallel connectionoperable to hold said filter taut under slight tension and to hold saidlever in a rest position wherein said releasable connection is closedwhereby movement oi said lever out of said rest position in oppositionto said spring operates to collapse said filter until said releasableconnection opens thereby allowing said spring to tension said filterabruptly and to thereafter return said lever to its rest position andclose said releasable connection.

DONALD G. SMELLIE.

REFERENCES CITED Number Number 8 UNITED STATES PATENTS Name Date SmithSept. 20, 1910 Dod Feb. 25, 1919 Cutter Sept. 22, 1925 Goodloe June 24,1930 Sutherland June 28, 1932 Forsberg Oct. 31, 1933 Lofgren Nov. 26,1935 Lofgren Apr. 20, 1937 Leathers Mar. 5, 1940 McAllister Aug. 20,1940 Leathers Dec. 8, 1942 Silverman et a1 Jan. 21, 1947 Segesman Feb.21, 1950 White Feb. 21, 1950 FOREIGN PATENTS Country Date Germany Mar.6, 1941

